Currently, smart devices are becoming increasingly richer in kinds and larger in quantity, and how to control these devices becomes a difficult problem. Especially with the emergence of the wearable devices which can be worn at different positions on a human body, the control over these devices becomes more and more difficult.
Currently, mobile phones are used to control on and off of various smart devices. However, with the size of the mobile phone becoming larger and larger, the operation becomes inconvenient. Especially when walking or conducting other activities, using a mobile phone to control the smart device becomes very inconvenient.